A battery of an electric or hybrid motor vehicle is charged by means of an externally accessible charging socket. During a charging process it should be possible to ensure that the corresponding charging plug inserted into the charging socket cannot be removed by an unauthorized person and that the charging process can be carried out safely.
A locking device for a charging socket and charging plug capable of giving protection against unauthorized removal of the charging plug is evident from document DE 196 42 687 A1. For this purpose, this locking device has an actuating element or actuator with which a locking bar can be adjusted to lock the charging plug. The actuator serves for locking a connection of a charging plug and a charging socket for charging the battery of an electric motor vehicle. This is done either by locking a pivoting lid, or by directly locking the charging plug. This device takes up a relatively large constructional volume. It can be optimized with regard to the protection against moisture.
Document DE 102 59 465 A1 discloses an actuator for a fuel filler lid lock of a motor vehicle with an electric motor capable of turning a spindle. A rotary movement of the spindle causes a linear displacement of a locking bar. The locking bar is sealed towards the outside by a bellows in order to protect the actuator against moisture and dirt. However, the bellows provides for a relatively large construction space.
Document DE 102 14 398 A1 discloses a device which can be used, for example, for locking/unlocking door locks of motor vehicles, the device being equipped with a shape-memory member.
In actuators with an electrically displaceable locking bar, there is the problem that there is no possibility of unlocking if the associated electrical or electronic system is damaged.